function PDE = PDE_struct_2d(exmple_index)

switch exmple_index
    case 1
        PDE.u = @(x,y) x.*y.*(1-0.5*x).*(1-y).*exp(x+y);
        PDE.dudx = @(x,y) 0.5*(y.*exp(y+x).*(x.^2-2.0).*(y-1.0));
        PDE.dudy = @(x,y) 0.5*(x.*exp(y+x).*(x-2.0).*(y+y.^2-1.0));
        PDE.cor = @(x,y) 1;
        PDE.f = @(x,y)-y.*(1-y).*(1-x-0.5*(x.^2)).*exp(x+y)-x.*(1-0.5*x).*(-3*y-y.^2).*exp(x+y);
        PDE.bdary = [0, 0, 0, 0];
    case 2
        PDE.u = @(x,y) exp(x+y);
        PDE.dudx = @(x,y) exp(x+y);
        PDE.dudy = @(x,y) exp(x+y);
        PDE.cor = @(x,y) 1;
        PDE.f = @(x,y) -2*exp(x+y);
        PDE.bdary = [1, 0, 0, 0];
    otherwise
        error("Invalid PDE exmple_index");
end

end